1. Field
Example embodiments relate to a nonvolatile memory device, a method of fabricating and a method of operating the same. For example, a nonvolatile flash memory device may have improved reliability and/or may secure an increased opposing area between control gate and floating gate electrodes, a method of fabricating and method of operating the nonvolatile flash memory device.
2. Description of the Related Art
Memory devices may have various applications in various apparatuses, for example, micro-controllers and credit cards. Memory devices may be classified into volatile memory devices and nonvolatile memory devices. Volatile memory devices may include dynamic random access memories (DRAMs) and static random access memories (SRAMs). The volatile memory devices may input and output data at higher speed, however, data in the volatile memory devices may disappear over time. On the other hand, non-volatile memory devices may permanently retain data, however, non-volatile memory devices may input and output data at lower speed. For example, flash memories and electrically erasable and programmable read-only memories (EEPROMs), which may electrically input and output data, have been developed as non-volatile memory devices.
Memory devices may increasingly be required to be more highly integrated, and a structure for programming multi-bit data in a cell may be developing.
As memory devices may become smaller with decreasing design rules, even a slight misalignment of floating gate electrodes or control gate electrodes may significantly deteriorate the performance of the memory devices, thereby undermining the reliability of the memory devices. In addition, because a smaller memory device may result in a smaller opposing area between control gate and floating gate electrodes, it may be difficult to secure sufficiently large capacitance between the control gate and floating gate electrodes. Therefore, a driving voltage may be increased.